The start codon is the first codon of a messenger RNA (mRNA) transcript translated by a ribosome.
Nitrogen base sequence for the start codon is AUG.
Radiation can actually affect the entire body, however it has a large effect of the bone marrow. Radiation is dangerous because too much can cause cellular depredation, this happens in environment that rapidly change like the bone marrow, which then interferes with blood cell production.
